Abstract:
Hardened concrete exposed to freeze-thaw cycles may be damaged under the form of internal frost and/or scaling. The last one is a complex phenomenon, which leads to superficial damage particularly in the presence of de-icing salt.

The French scaling standard test requires 56 freeze-thaw cycles with a 3% sodium chloride solution laid on the exposed surface of the concrete. The result is expressed as the scaled mass related to the exposed surface. A quantitative statistical-based analysis with 3 different concrete mix compositions allows us to establish that these results follow lognormal distributions. This distribution law correctly translates the asymmetry and the observed dispersion. But it also shows that the standard test can discriminate high from weak resistant concrete.

A new method to analyse these results is to evaluate the number of freeze-thaw cycles necessary to reach a fixed scaled mass. These last results are distributed according to a normal distribution. This distribution is centered around an identifiable number of freeze-thaw cycles which is one of the major parameters of the deterioration. Furthermore, this new method to analyse the scaling test shows that it is possible to decrease the coefficient of variation for a higher number of cycles.